At least six persons, including a 15-year-old boy, were killed and 80 injured on Monday night as suspected terrorists set off bomb blasts in the communally-sensitive town of Malegaon in Maharashtra and Modasa town in Gujarat's Banaskantha district.

Curfew was imposed in the eastern part of communally sensitive powerloom town of Malegaon town after the blast and stone-pelting by a mob.

Four persons perished and more than 70 were injured when a bomb went off at a hotel near a mosque at busy Bhikhu Chowk area in Malegaon, police sources said.

A silver-coloured motorcycle was found parked near the site of the blast, police said.

The mob pelted stones on police force and jeep of the sub-divisional-magistrate was also damaged in the stone-pelting, police said.

Police also fired in the air to disperse the crowd.

Five policemen, including additional SP Viresh Prabhu, were among the injured in the stone-pelting by the irate mob, police said.

In Modasa, a 15-year-old and another person were killed and 9 others were injured when an explosive device fitted to a motorcycle went off, Banaskantha district SP R B Brahmbatt said.

"Our primary investigation shows that two guys had kept a bag on a parked motorcycle which exploded. Suka Bazar is a congested area," he said.

"Over 20,000 people gathered at the spot where the blast took place. We have rushed State Reserve Police Forcepersonnel to Malegaon," Patil, who also holds the Home portfolio, told reporters.

"At this moment it is difficult to say whether the blast was an accident or a deliberate ploy to create panic," Patil said, adding an Anti-Terrorism Squad (ATS) team has also rushed to the spot in North Maharashtra.